Bronchial allergen challenge - An old, but still useful tool in research and diagnostics

A bronchial allergen challenge may serve both as a diagnostic as well as investigative procedure. Its usage in the diagnosis of asthma is infrequent due to its time-consuming nature as well as (in our opinion) an unfounded fear for a patient's safety. It is quite useful in the diagnostics of workplace related illnesses. Due to its ability to produce a controlled, long-lasting allergic-inflammatory reaction in the bronchi, this procedure is commonly used in research settings as well as in the assessment of new substances which may potentially have a place in the treatment of asthma, for ex. through the blocking of late asthmatic reactions. Changes stimulated by a bronchial allergen challenge may be evaluated by many methods using different materials, i.e. samples obtained from direct biopsies, bronchoalveolar lavages, exhaled breath condensates, or measured fractional exhaled nitric oxide. This procedure is a seemingly ideal research and diagnostic tool, however, a common protocol for its execution has not yet been accepted. Recent legal regulations have resulted in difficulties obtaining various allergens for challenge tests. Hopefully this is a temporary and minor setback for this very useful and constantly developing procedure.